Submission #880188

#	Time	Username	Problem	Language	Result	Execution time	Memory
880188		cpptowin	Bitaro’s Party (JOI18_bitaro)	C++17	0 / 100	19 ms	50012 KiB

bitaro

#include<bits/stdc++.h>
#define fo(i,d,c) for(int i=d;i<=c;i++)
#define fod(i,c,d) for(int i=c;i>=d;i--)
#define maxn 1000010
#define N 1010
#define fi first
#define se second
#define pb emplace_back
#define en cout<<"\n";
#define int long long
#define inf 1000000000
#define pii pair<int,int>
#define vii vector<pii>
#define lb(x) x&-x
#define bit(i,j) ((i>>j)&1)
#define offbit(i,j) (i^(1<<j))
#define onbit(i,j) (i|(1<<j))
#define vi vector<int>
template <typename T1, typename T2> bool minimize(T1 &a, T2 b){if (a > b) {a = b; return true;} return false;}
template <typename T1, typename T2> bool maximize(T1 &a, T2 b){if (a < b) {a = b; return true;} return false;}
using namespace std;
int n,m,q;
const int nsqrt = 450;
vi ke[maxn];
vii d[maxn];
int dist[maxn];
bool ok[maxn];
bool vis[maxn];
int from[maxn];
int val[maxn];
void dfs(int u)
{
    vis[u] = 1;
    for(int v : ke[u])
    {
        if(vis[v]) continue;
        dist[v] = dist[u] + 1;
        dfs(v);
    }
}
main()
{
    #define name "TASK"
    if(fopen(name".inp","r"))
    {
       freopen(name".inp","r",stdin);
       freopen(name".out","w",stdout);
    }
    ios_base::sync_with_stdio(false);cin.tie(NULL);
    cin >> n >> m >> q;
    fo(i,1,m)
    {
        int u,v;
        cin >> u >> v;
        ke[v].pb(u);
    }
    fo(u,1,n)
    {
        vi now;
        for(int v : ke[u])
        {
            for(auto [z,t] : d[v])
            {
                if(from[z] == u)
                {
                    val[z] = max(val[z],t + 1);
                }
                else
                {
                    from[z] = u;
                    val[z] = t + 1;
                    now.pb(z);
                }
            }
        }
        d[u].pb(u,0);
        for(int it : now) d[u].pb(it,val[it]);
        sort(d[u].begin(),d[u].end(),[](pii a,pii b)
             {
                 return a.se > b.se;
             });
        if(d[u].size() > nsqrt) d[u].erase(d[u].begin() + nsqrt,d[u].end());
    }
//    fo(i,1,n)
//    {
//        for(auto [u,v] : d[i]) cout << u << ' ' << v << "\n";
//    }
    while(q--)
    {
        int t,s;
        cin >> t >> s;
        vi bad(s);
        for(int &it : bad)
        {
            cin >> it;
            ok[it] = 1;
        }
        if(s > nsqrt)
        {
            int ans = 0;
            fo(i,1,n) vis[i] = dist[i] = 0;
            dfs(t);
            fo(i,1,n) if(!ok[i]) ans = max(ans,dist[i]);
            cout << ans;en;
        }
        else
        {
            for(auto [i,j] : d[t])
            {
                if(!ok[i])
                {
                    cout << j << "\n";
                    break;
                }
            }
        }
        for(int it : bad) ok[it] = 0;
    }
}

Compilation message (stderr)

bitaro.cpp:41:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   41 | main()
      | ^~~~
bitaro.cpp: In function 'int main()':
bitaro.cpp:101:40: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
  101 |             fo(i,1,n) vis[i] = dist[i] = 0;
      |                                ~~~~~~~~^~~
bitaro.cpp:46:15: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   46 |        freopen(name".inp","r",stdin);
      |        ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
bitaro.cpp:47:15: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   47 |        freopen(name".out","w",stdout);
      |        ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 7
• Subtask 2: 0 / 7
• Subtask 3: 0 / 86